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Pioneer SX-650 Restoration Project

Timothy Flath

Timothy Flath

Well-Known Member
A while back my lovely wife found a nice little toy at a local thrift shop so I got her to bring it home (love that she gives me a call when she sees something nice). Was really needing a nice little project to keep me occupied with Omicron raging out there these days. Ordered a Deluxe restoration kit with all caps (including large smoothing caps), problematic trannies kit and even a relay all for a decent price from the US (I am in Canada - Voctoria, BC). This was the initial cleanup work to get it all working nice. Can't wait to dig in when the parts arrive. Certainly not as big and desirable as the SX-950 I did this past summer but it will be a good time waster me thinks. Plan will be to post this as a video series like I did with my SX-950 receiverthis past summer. As always constructive comments and suggestions are always welcome. So without further adieu, this is part 1:

 
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Looking through the baggy I got for the Phono circuit (in the kit) I cannot for the life of me figure out why there are the following transistors in the Phono circuit bag? Very puzzling:confused: As far as I can make out there is no triple set of the same transistors anywhere in the phono circuits or on the Tuner and AF Assembly (AWE-075-A) Board schematic:

A992 X 3 Transistors
FBCA37

JCC1
845F X 1 Transistor
N42

Any ideas where these Trannies go? Thinking they might turn up on another board down the line???? Will go back to kit seller and ask I guess - his baggy lableing is seriously confusing. I have done a few other kits and this is by far the worst. Usually I get a parts list to check against the various boards. This time I got a bunch of incorrectly labeled baggies with some missing or incorrect sizes and under-voltage rated caps. The ones I did receive were all high quality Nichicons but....
 
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the 992 at Q 1 , 2 and 4
the 1845 at Q3

100_8002.JPG

you may not have that board.
you may have the IC board

100_8001.JPG

IC board pic

Pioneer SX-650_Phono Equalizer Amp_After servicing.jpg
 
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Timothy Flath said:
Will go back to kit seller and ask I guess - his baggy lableing is seriously confusing. I have done a few other kits and this is by far the worst. Usually I get a parts list to check against the various boards. This time I got a bunch of incorrectly labeled baggies with some missing or incorrect sizes and under-voltage rated caps. The ones I did receive were all high quality Nichicons but....
Click to expand...

Whose kit did you get? If it has this many issues, you should have sent it back.
 
EastPoint said:
Whose kit did you get? If it has this many issues, you should have sent it back.
Click to expand...
He had forgot to include his parts list and quickly rectified that this AM with an email. I was wondering why I had extra parts - it is because he includes parts for multiple versions with sometimes differing boards. He was willing to rectify the Wima caps shotcoming but I said not to bother as I had suitable replacements on hand. He is updating his list for naming conventions as well - all was explained in the parts list anyway so I am now a very happy camper.:beerchug:
 
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Following, Appreciate your documentation.

My SX-650 waits patiently for attention but am enjoying listening to it in the meantime.
 
EastPoint said:
You said there were a bunch of caps with voltages that were too low, right? Did he fix that?
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Actually only two - yes he did offer to rectify. In actual fact the schematic called for the voltage provided. The pulled ones were of higher voltage as is often the case so I was going by that so my bad
 
Part 3 just completed - Phono sounds pretty Rockin'!!!!
Some of the original (larger value) caps were quite far out of tolerance...

 
What are folks thoughts on applying the Tuner kit as discussed in the above video starting at 12 min 35 seconds in? I have done tuner cap and tranny swaps - most notably the one below for my trusty TX-8500II with no detrimental effects but I feel I might be pushing my luck with this one given the number of Caps and Transistors it will swap out. Merely looking for opinions but as I sit here typing I am listening to the radio on the SX-650 down here in my basement and it is sounding pretty darn good. I am leaning towards leaving it not because I am lazy but rather because I can always fix it later if it comes to that...:confused:

 
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